An association between residual vein thrombosis and subclinical atherosclerosis: Cross-sectional study

BACKGROUND

The association between venous and arterial thrombotic disorders is still unclear. We assessed the association between residual vein thrombosis (RVT) and subclinical atherosclerosis in a cohort of patients with unprovoked (or associated with weak risk factors) proximal deep-vein thrombosis (DVT).

METHODS

In a multicenter cross-sectional study, consecutive patients over 40years free from atherosclerotic disorders received the ultrasound assessment of the leg vein system and that of carotid arteries approximately three months after an episode of proximal DVT. In each center the evaluation was done by two independent assessors. The presence of RVT was defined as the incompressibility of at least 4mm in either the popliteal or the common femoral vein, and that of subclinical atherosclerosis as the presence of increased (>0.9mm) intima-media tickness (IMT) and/or carotid plaques.

RESULTS

Out of 252 patients (mean age, 67; males, 53%; unprovoked, 77%), the presence of RVT was found in 139 (55.2%). An increased IMT was shown in 76 (54.7%) patients with and in 35 (31.0%) without RVT (p<0.001). At least one carotid plaque was found in 80 (57.6%) patients with and in 36 (31.9%) without RVT (p<0.001). After adjusting for the baseline characteristics, the odds ratio of subclinical atherosclerosis (increased IMT and/or carotid plaques) was 2.8 (95% CI, 1.6 to 4.7).

CONCLUSION

The ultrasound detection of RVT after an episode of proximal DVT that is either unprovoked or triggered by weak risk factors is associated with a higher prevalence of subclinical atherosclerosis. These findings may have implications for patient prognosis.

A venous thromboembolism risk assessment model for patients with Cushing's syndrome

Cushing's syndrome (CS) is associated with an incidence of venous thromboembolism (VTE) about ten times higher than in the normal population. The aim of our study was to develop a model for identifying CS patients at higher risk of VTE. We considered clinical, hormonal, and coagulation data from 176 active CS patients and used a forward stepwise logistic multivariate regression analysis to select the major independent risk factors for thrombosis. The risk of VTE was calculated as a 'CS-VTE score' from the sum of points of present risk factors. VTE developed in 20 patients (4 pulmonary embolism). The group of CS patients with VTE were older (p < 0.001) and had more cardiovascular events (p < 0.05), infections and reduced mobility (both p < 0.001), higher midnight plasma cortisol levels (p < 0.05), and shorter APTT (p < 0.01) than those without. We identified six major independent risk factors for VTE: age ≥69 years and reduced mobility were given two points each, whereas acute severe infections, previous cardiovascular events, midnight plasma cortisol level >3.15 times the normality and shortened APTT were given one point each. A CS-VTE score <2 anticipated no risk of VTE; a CS-VTE score of two mild risk (10 %); a CS-VTE score of three moderate risk (46 %); a CS-VTE score ≥4 high risk (85 %). Considering a score ≥3 as predictive of VTE, 94 % of the patients were correctly classified. A simple score helps stratify the VTE risk in CS patients and identify those who could benefit from thromboprophylaxis.

Determination of the longest intrapatient left ventricular electrical delay may predict acute hemodynamic improvement in patients after cardiac resynchronization therapy

BACKGROUND

One of the reasons for patient nonresponse to cardiac resynchronization therapy is a suboptimal left ventricular (LV) pacing site. LV electric delay (Q-LV interval) has been indicated as a prognostic parameter of cardiac resynchronization therapy response. This study evaluates the LV delay for the optimization of the LV pacing site.

METHODS AND RESULTS

Thirty-two consecutive patients (23 men; mean age, 71±11 years; LV ejection fraction, 30±6%; 18 with ischemic cardiomyopathy; QRS, 181±25 ms; all mean±SD) underwent cardiac resynchronization therapy device implantation. All available tributary veins of the coronary sinus were tested, and the Q-LV interval was measured at each pacing site. The hemodynamic effects of pacing at different sites were evaluated by invasive measurement of LV dP/dtmax at baseline and during pacing. Overall, 2.9±0.8 different veins and 6.4±2.3 pacing sites were tested. In 31 of 32 (96.8%) patients, the highest LV dP/dtmax coincided with the maximum Q-LV interval. Q-LV interval correlated with the increase in LV dP/dtmax in all patients at each site (AR1 ρ=0.98; P<0.001). A Q-LV value >95 ms corresponded to a >10% in LV dP/dtmax. An inverse correlation between paced QRS duration and improvement in LV dP/dtmax was seen in 24 patients (75%).

CONCLUSIONS

Pacing the LV at the latest activated site is highly predictive of the maximum increase in contractility, expressed as LV dP/dtmax. A positive correlation between Q-LV interval and hemodynamic improvement was found in all patients at every pacing site, a value of 95 ms corresponding to an increase in LV dP/dtmax of ≥10%.

Hisian area and right ventricular apical pacing differently affect left atrial function: an intra-patients evaluation

AIMS

Right ventricular apex (RVA) pacing has adverse effects on left atrial (LA) function and may contribute to atrial arrhythmias. The effects of Hisian area (HA) pacing on LA function are still lacking. The objective of this study is to assess the left ventricular (LV) electromechanical activation/relaxation, systolic (S), diastolic (D) phases, and their effects on LA function during pacing from HA and RVA.

METHODS AND RESULTS

Thirty-seven patients with normal cardiac function underwent permanent HA pacing. In all patients, a RVA backup lead was added. The patients first underwent 3 months of HA pacing, followed by 3 months of RVA pacing. After each 3-month period, we compared by echocardiography: S-D LV electromechanical delay (S-D EMD), S-D intra-LV dyssynchrony, LV S-D phases, and their function evaluated by myocardial performance index (MPI) and mitral annular tissue Doppler early diastolic velocity (E'), pulmonary arterial systolic pressure (PASP), and LA function (LA phasic volumes and their emptying fraction). Right ventricular apex compared with HA pacing increased S-D EMD (P < 0.001) and intra-LV dyssynchrony (P < 0.001). As a consequence, a significant longer LV isovolumetric contraction time (P < 0.001) and LV isovolumetric relaxation time (P = 0.05) were measured during RVA compared with HA pacing, whereas LV ejection time was shorter (P = 0.033). Moreover, HA pacing resulted in significantly better MPI (P = 0.039), higher value of E' (P = 0.049), and lower PASP (P < 0.001). Finally, RVA compared with HA pacing was associated to higher LA volumes pre-atrial contraction (P = 0.001) and minimal volume (P = 0.003) with reduction in passive emptying fraction (P < 0.001) and total emptying fraction (P = 0.005).

CONCLUSION

Hisian area compared with RVA pacing resulted in a more physiological LV electromechanical activation/relaxation and consequently better LA function.

How can we identify the optimal pacing site in the right ventricular septum? A simplified method applicable during the standard implanting procedure

AIMS

A short paced (p) QRS duration (d) can be a marker for selecting the most appropriate RV pacing site. Although this could be achieved by continual 12-Lead ECG monitoring, such a technique is not applicable during pacemaker (PM) implantation. The purpose of this study was to validate a method for identifying the optimal site for RV septum pacing using simple markers derived from few real-time ECG leads and fluoroscopy (F).

METHODS AND RESULTS

An overall of 304 measurements of pQRSd in different RV sites was performed in 102 patients undergoing PM implant. In accordance with F position the lead placement was classified high, medium, and low septum. Paced electrocardiographic/fluoroscopic parameters (q-wave/negative QRS in lead I, notching in limb leads, R/S wave in lead II, QRS precordial leads transition, and F septal segments pacing site) were analyzed to predict short pQRSd (≤ 160 ms). Logistic regression analysis showed that pQRSd > 160 ms was predicted by presence of pQRS notching in limb leads (OR = 3.24, p < 0.001), and with negative amplitude of QRS in lead II (OR = 2.53, p = 0.03). Short pQRSd (≤ 160 ms) was observed with mid F position (OR = 0.31, p < 0.001) and with the presence of a q-wave/negative QRS in lead I.

CONCLUSION

In RV septum pacing, simple QRS markers of few limb leads (lead I/II) added to F position are usefull to identifying the optimal site to place the RV lead.

Aspirin and recurrent venous thromboembolism

While there is conclusive evidence that aspirin plays a role in reducing the risk of clinically relevant venous thromboembolism (VTE) arising in a number of surgical and non-surgical situations at risk, little is known of the potential of aspirin for the long/term prevention of recurrent VTE. In two recent multicentre, double-blind studies (WARFASA and ASPIRE), the efficacy and safety of a low dose of aspirin (100 mg per day) were assessed in patients with unprovoked VTE who had completed an initial period of conventional treatment with vitamin K antagonists. The two studies used identical aspirin regimens and had similar enrollment criteria and outcome measures. When data from these two trials were pooled, there was a 32% reduction in the rate of recurrence of VTE (hazard ratio [HR], 0.68; 95% confidence interval [CI], 0.51-0.90) and a 34% reduction in the rate of major vascular events (HR, 0.66; 95% CI, 0.51-0.86). Moreover, these benefits were achieved with a low risk of bleeding. As patients with previous symptomatic atherosclerosis were not enrolled in these two studies, whether these results apply also to this category of patients is uncertain. We recently had the opportunity to review the clinical charts of 1919 consecutive patients presented with a first episode of VTE, which was either unprovoked or triggered by transient risk factors, and were followed up for an average period of four years after discontinuing anticoagulation. The rate of recurrent VTE in the 256 patients with a history of symptomatic atherosclerosis who had been given 80-160 mg of aspirin once daily (17.2%) did not differ from that (19.9%) observed in those without atherosclerosis who were left without any antithrombotic treatments. The implication of this observation is that whenever patients with symptomatic atherosclerosis are deemed to require long-term protection against recurrent VTE, they are unlikely to benefit from (resuming) aspirin. Conversely, aspirin in low doses offers an appealing, safe and highly cost-effective option for the long-term prevention of recurrent events in patients with unprovoked VTE who are free from symptomatic atherosclerotic lesions.